Study Questions:

What is the yield of cardiac testing in children with a family history of sudden death, and are there clinical predictors of a cardiac diagnosis?

Methods:

This was a retrospective cohort study of all patients undergoing cardiac evaluation for family history of sudden death at a single large tertiary pediatric center between 1999 and 2016. Logistic regression models were utilized to associate predictors with the outcomes of interest.

Results:

There were 419 pediatric patients evaluated as relatives of 256 decedents. The primary diagnostic outcomes of interest in the evaluated patients were: 1) heritable diagnosis associated with sudden death (i.e., long QT syndrome [LQTS], hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy) found in 9.3% of patients; and 2) findings of uncertain significance (i.e., intraventricular conduction delay, abnormalities potentially related to but not diagnostic of LQTS, ventricular hypertrophy or dilation, and others) in 12.4%. Multiple regression identified two strong predictors of finding a heritable cardiac diagnosis – any abnormal electrocardiogram (ECG) and decedent was a first-degree relative. The negative predictive value of the ECG was 98%. Echocardiography was also frequently useful, but not ideally predictive of health or disease. The utility of other testing such as exercise test or provocative drug testing was limited.

Conclusions:

Pediatric patients evaluated for a family history of sudden death had a 9% risk of having a heritable cardiac disease and a 14% risk of having a finding of uncertain significance.

Perspective:

Countries with centralized medical records will frequently have systematic methods of assuring that family members of sudden death victims are adequately evaluated for heritable conditions. In the United States, this responsibility falls on to the primary physicians, medical examiners, or other involved providers; though not all may be aware of the importance of evaluating family members for a risk of sudden death. This study provides useful data to enthuse more proactive investigation into sudden death and subsequent cascade evaluation, especially of children. The one shortcoming in the study is the speculation that the ‘findings of unknown significance’ are clinically important. Follow-up outcomes on patients with these findings would be of interest, but are not provided despite the 17-year study period. This information is perhaps planned for a future publication.